Under the action of variable force, the trajectory of an object can not be a parabola Is that correct? Why

Under the action of variable force, the trajectory of an object can not be a parabola Is that correct? Why

If the trajectory wants to be a parabola, it must move in a straight line with uniform velocity in one direction and in a straight line with uniform acceleration in the other vertical direction. It is impossible to know if the object is subjected to variable force, so this statement is correct

What is the condition for the trajectory of an object to be a parabola?
Please don't take flat throw as an example=
What I want to ask is
Is it the initial velocity of an object as long as it is subjected to a constant resultant force and the resultant force is not in the same straight line
Can we deduce that the trajectory of this object is a parabola?
Is there a condition that the resultant force must be perpendicular to the initial velocity?
If you answer yes, you'll get extra points. Thank you

[is it the initial velocity of an object as long as it is subjected to a constant resultant force and the resultant force is not in the same straight line]
That's right
The direction of resultant force and initial velocity does not have to be perpendicular
As long as they are not collinear

When the force of an object satisfies what conditions, is the trajectory a parabola? Is the trajectory a parabola when a constant force (with or without initial velocity in this direction) and initial velocity in another vertical direction are applied in one direction?

The resultant force is constant and there is at least one initial velocity which is not collinear with the direction of resultant force

Are the trajectories of horizontal throwing parabola?

Of course, the parabola is the trajectory of the object